Figure 6. Incorporation of lasR mutant at appropriate proportion can maximize population size under nutrient decreased conditions.

Different mixtures of WT PAO1 with lasR deletion mutant (a), as well as with the randomly selected lasR mutants lasR2 (b), lasR3 (c), and lasR4 (d) in this study, were inoculated into gradient M9-caseinate medium and co-cultured for 36 h, respectively. Mean values ± SEM of one experiment are shown and are representative of three independent experiments. The experiments of panels a, b and d showed significantly (P < 0.05) increased cell density when caseinate levels were lower than 0.5% and the frequency of cheater (lasR mutant) is 50%.